REV09040

• Permit No: C1981018
• IBM Index Class Name: Revision
• Doc Date: 4/7/1993
• Doc Name: MEMO DESERADO MINE C-81-018 TR-31
• From: DMG
• To: JANET BINNS
• Type & Sequence: TR31
• Media Type: D
• Archive: No

ii i iiiiu i iiiiii iii
999
STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Department of Natural Resources
1313 Sherman St., Room ? 15
Denver, CO v0?03
Phone: U03) R6F,-3567
FAX:IloJl BJ'~tll U6
DATE: April 07, 1993
MEMO
TO: Janet Binns
FROM: Susan Morrison ~ti4~~~
RE: Deserado Mine (C-81-018)
Technical Revision 31
of cow
R~ _ -0
~~~~
n
.~1~.
.t
/¢'!e
Roy Romer
Goremor
.Michael B. Lung
Division Direuor
Following are my concerns and requests after an adequacy review of WFU's response to my
memo of February 24, 1993. I requested these items in a telephone conversation with Dave
Anderson of WFU on March 24, 1993.
1. In order to verify the volume of the pond, we are still in need of a detailed topographic
map or drawing of the pond as it will be constructed.
2. WFU included a commitment to certify, upon completion of construction, that the pond
was constructed as designed. In order to accomplish this, a detailed design should first
be submitted, again, in the form of a detailed topographic drawing.
3. The "SDH #4 Discharge Layout" submitted by WFU shows the top of the SDH#4 pond
embankment at 5410'. Map 141, submitted with the topographic drawing, shows the top
of the embankment at 5412'. The discharge layout drawing shows the pond bottom
somewhere between 5410' and 5420', Map 141 shows a bottom elevation of 5407'.
WFU should revise one or both of these drawings to accurately reflect the proposed
design.
4. The scales shown on the drawings which are printed on 8L/z" X 11" paper do not
coincide with the written scales. Please have WFU correct these discrepancies.
5. Map 141 shows rip rap on the slope below the primary discharge pipe. WFU should
include details on sizing of the rip rap, and what inputs were used to determine sizing.